package com.qipay.core.qrcode;

import com.google.zxing.*;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxing.common.BitMatrix;
import com.google.zxing.common.HybridBinarizer;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ColorConvertOp;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Map;

public class QRCodeUtils {

    private static final int BLACK = 0xFF000000;
    private static final int WHITE = 0xFFFFFFFF;

    private static final String CHARSET = "UTF-8";

    private static final String FORMAT_NAME = "JPG";

    // LOGO宽度
    private static final int WIDTH = 60;

    // LOGO高度
    private static final int HEIGHT = 60;

    private QRCodeUtils() {
    }
    private static BufferedImage toBufferedImage(BitMatrix matrix) {
        int width = matrix.getWidth();
        int height = matrix.getHeight();
        BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
        for (int x = 0; x < width; x++) {
            for (int y = 0; y < height; y++) {
                image.setRGB(x, y, matrix.get(x, y) ? BLACK : WHITE);
            }
        }
        return image;
    }

    private static void writeToFile(BitMatrix matrix, String format, File file) throws IOException {
        BufferedImage image = toBufferedImage(matrix);
        if (!ImageIO.write(image, format, file)) {
            throw new IOException("Could not write an image of format " + format + " to " + file);
        }
    }

    private static void writeToStream(BitMatrix matrix, String format, OutputStream stream) throws IOException {
        BufferedImage image = toBufferedImage(matrix);
        if (!ImageIO.write(image, format, stream)) {
            throw new IOException("Could not write an image of format " + format);
        }
    }

    /**
     * 生成QRCode的图片到OutputStream中
     * @param content 二维码内容
     * @param width 宽度
     * @param height 高度
     * @param format 输出格式
     * @param stream 输出流
    */
    public static void createQRCodeImageStream(
            String content,
            int width,
            int height,
            String format,
            OutputStream stream
    ) throws WriterException, IOException {
        Hashtable<EncodeHintType, String> hints = new Hashtable<>();
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        BitMatrix bitMatrix=new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, width, height, hints);
        writeToStream(bitMatrix,format,stream);
    }

    /**
     * 生成QRCode的图片到OutputStream中
     * @param content 二维码内容
     * @param stream 输出流
     */
    public static void createQRCodeImageStream(
            String content,
            OutputStream stream
    ) throws WriterException, IOException {
        Hashtable<EncodeHintType, String> hints = new Hashtable<>();
        hints.put(EncodeHintType.CHARACTER_SET, CHARSET);
        BitMatrix bitMatrix=new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, WIDTH, HEIGHT, hints);
        writeToStream(bitMatrix,FORMAT_NAME,stream);
    }

    /**
     * 解析二维码，获取url
     * @param file
     * @return
     */
    public static String getQRCodeUrl(File file){
        Result result = null;
        try {
            MultiFormatReader formatReader = new MultiFormatReader();
            //读取指定的二维码文件
            BufferedImage bufferedImage =ImageIO.read(file);
            BinaryBitmap binaryBitmap= new BinaryBitmap(
                    new HybridBinarizer(new BufferedImageLuminanceSource(bufferedImage)));
            //定义二维码参数
            Map hints= new HashMap<>();
            hints.put(EncodeHintType.CHARACTER_SET, "utf-8");
            result = formatReader.decode(binaryBitmap, hints);
            //输出相关的二维码信息
            bufferedImage.flush();
        } catch (NotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result==null?"":result.getText();
    }

    /**
     * 切换彩色图片为黑白色
     * @param f
     */
    /*public static void changeImge(File f) {
        try {
            Image image = ImageIO.read(f);
            int srcH = image.getHeight(null);
            int srcW = image.getWidth(null);
            BufferedImage bufferedImage = new BufferedImage(srcW, srcH,BufferedImage.TYPE_3BYTE_BGR);
            bufferedImage.getGraphics().drawImage(image, 0,0, srcW, srcH, null);
            bufferedImage=new ColorConvertOp(ColorSpace.getInstance(ColorSpace.CS_GRAY),null).filter (bufferedImage,null);
            FileOutputStream fos = new FileOutputStream(f);
            JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(fos);
            encoder.encode(bufferedImage);
            fos.close();
            // System.out.println("转换成功...");
        } catch (IOException e) {
            e.printStackTrace();
            throw new IllegalStateException("图片转换出错！", e);
        }
    }*/
}
